Yes, the U.S. really is preparing to drop millions of flies from airplanes — and it may be the only way to save its cattle industry.
Sounds like science-fiction? It’s not. Government documents show that the U.S. Department of Agriculture (USDA) has already green-lit an aerial campaign to release sterile male New World screwworm flies along the Texas–Mexico border. Far from a horror plot, the plan revives a Cold-War–era technique that once wiped the flesh-eating parasite out of North America.
But as we dug into the facts, one twist jumped out: the “new fly factory” many headlines trumpet isn’t a factory at all. It’s a dispersal base that will receive lab-reared insects from Panama, load them into planes, and push them out the door. Production remains more than 1,500 miles away.
Below, we unpack what’s real, what’s exaggerated, and why time is running out.
The Parasite at the Gate
Imagine a blowfly whose larvae burrow into a cut on a calf, eat living flesh, and keep eating until the animal dies unless a rancher spots the wound in time. That’s Cochliomyia hominivorax, the New World screwworm.
• Victims: cattle, horses, wildlife, pets — and, rarely, humans
• Egg output: 200–300 per female, often laid in a single wound
• Fatal timeline: untreated animals can die in roughly 7–10 days (the “within a few days” line you may have read is slightly dramatic but not wildly off)
• Treatment options: no vaccine; daily wound checks, insecticide sprays, or—and this is the big one—release of sterile males
Why Bring Back a 1960s Playbook?
In the 1960s and ’70s, the USDA flooded infested areas with male flies that had been irradiated until they were sterile. Females mated once, laid eggs that never hatched, and the species collapsed across the U.S. by 1966 and most of Mexico by 1991.
Today the screwworm is marching north again:
- 2023: Outbreak explodes in Panama (≈6,500 cases).
- 2024: Larvae found in Nicaragua, Honduras, Guatemala.
- 2025: Mexico reports cases just 370 miles from Texas.
(source: APHIS outbreak map)
Re-establishment in Texas alone could cost ranchers $1.9 billion a year, warns the American Farm Bureau. National losses would soar even higher.
The Plan: Drop, Mate, Eradicate
Verified: On 18 June 2025 the USDA announced an $8.5 million sterile-fly dispersal base at Moore Air Base, South Texas. Planes stationed there will release millions of sterile males every week into northern Mexico, creating a mating “fog” that should crash the population before it crosses the Rio Grande.
(USDA press release)
Correction to the viral headline:
• The South-Texas site will not produce the insects. All flies will be shipped in coolers from the COPEG plant in Pacora, Panama — currently the only screwworm factory on Earth.
• USDA says it is studying a full U.S. production plant, but the decision and funding are still pending.
How Do You “Make” a Sterile Fly?
- COPEG technicians rear screwworms on a ground-beef diet.
- Male pupae pass through a low-dose cobalt-60 radiation unit.
- Emerged adults are boxed, chilled, and flown north.
- Texas crews load the insects into hopper planes fitted with slow-release chutes.
- At 1,500 ft, the flies drift into the warm air — ready to romance their wild cousins, but genetically doomed to failure.
This “sterile-insect technique” is species-specific: it targets screwworms alone, leaving bees, butterflies, and other insects unharmed.
What Could Go Wrong?
Even USDA officials admit uncertainties:
• Production bottleneck: Panama’s plant can churn out ~117 million sterile flies a week. Experts estimate twice that might be needed if the outbreak reaches northern Mexico’s dense ranch lands.
• Border logistics: Sterile males live only about five days; shipping delays could render them useless.
• Mutation risk: Scientists insist radiation doses are calibrated to avoid creating hardy super-flies, but long-term monitoring continues.
“These aren’t ‘Franken-flies,’” says Dr. Phillip Kaufman, head of entomology at Texas A&M. “They’re normal males who happen to be very bad at fatherhood.”
Ranchers Caught Between Panic and Déjà Vu
Stephen Diebel, vice-president of the Texas & Southwestern Cattle Raisers Association, remembers old photos of calves eaten alive. “One pregnant cow infested with screwworms can infect an entire pasture,” he tells us. “We have to stay ahead of this.”
Yet some Texans bristle at the image of government planes raining insects:
• Social-media rumors call it “insect chem-trails.”
• Local officials worry about public pushback if dead flies litter porches.
USDA’s outreach teams now host town-hall meetings, passing around sealed vials of the harmless males to demystify the program.
Bottom Line: Horror-Story Headline, Science-Based Reality
✓ True: The U.S. will airdrop hundreds of millions of sterile male screwworm flies.
✓ True: The larvae can kill livestock and occasionally humans.
✗ Overstated: A “new fly factory” on the Texas border. It’s a logistics hub, not a breeding facility — at least for now.
≈ Slightly exaggerated: “Animals die in a few days.” Veterinary data say 7–10 days if untreated.
Everything else? Backed by decades of entomology and a successful eradication record.
What Happens Next?
• Fall 2025: First sterile-fly sorties from Moore Air Base.
• 2026: Decision on building a full U.S. production plant.
• 2027–28: Target date for declaring northern Mexico screwworm-free—if the plan works.
Should the parasite slip past the aerial shield, costs could dwarf the price of flights and radiation gear. For now, ranchers, entomologists, and taxpayers alike have a stake in a solution that sounds bizarre but has history on its side.
Until then, if you look up and see a small plane tracing grids over the chaparral, remember: the tiny specks falling out of the hatch are would-be fathers on a mission to save millions of animals — by never becoming fathers at all.